Jan:
Sorry I don't know the answer. My experience with this board is that a person will get good quick answers about all Mercedes models imported to the USA but questions about models only sold in Europe like your Vito and most Mercedes commercial vehicles often go unanswered because nobody knows the answer. There is a Mercedes bulletin board based in the UK although I don't have access to its URL at the moment. You are more likely to get an answer to your question there.